code: def reset(self):
      self.sum = {v: 0 for v in self.topk}
      self.n = 0
  
file_path: pywick/pywick/meters/classerrormeter.py
imports: import numpy
  import torch
  import numbers
  from .None import meter
label_desc: Use image node_id 2 for calling the ClassErrorMeter obj's underlying member method code with example usage: obj.reset() without return types